Membranes are used in a variety of methods for detecting or transferring biological materials, such as western blotting (for proteins), northern blotting (for RNA), and southern blotting (for DNA). In these various detection or transfer methods, the biological material of interest adheres to the membrane, e.g., a polyvinylidene fluoride membrane, which is then typically subjected to a detecting reagent, e.g., a dye or stain, which preferentially adheres to the biological material of interest so as to enable detection of the biological material. Many detecting reagents, however, also generally adhere, at least to some extent, to the porous membrane, particularly a polyvinylidene fluoride membrane, thereby increasing the background noise and decreasing the sensitivity or signal-to-noise ratio for detecting the biological material of interest.
Thus, there remains a need for improving those methods of detecting biological materials which utilize membranes in conjunction with detecting reagents, particularly by reducing the tendency of detecting reagents to adhere directly to such membranes. The present invention provides such an improvement through the use of a modified polyvinylidene fluoride membrane which exhibits reduced background noise. These and other objects and advantages of the present invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.